1. Field of the Invention
The present invention relates to an optical member in which generation of break of adhesives, surface pollution, etc. in a side face of an adhesive layer prepared in an optical material is prevented.
2. Description of the Background Art
Optical materials used for manufacturing of a liquid crystal display (LCD) etc., such as a polarizing plate and a retardation plate are practically used in a form of optical members comprising a laminated body in which adhesive layers are prepared in optical materials beforehand, for example; elliptically polarizing plates to which a polarizing plate and a retardation plate are laminated through adhesive layers beforehand; and optical members in which adhesive layers for being adhered with other members such as liquid crystal cell etc. are attached beforehand to a polarizing plate, in order to prevent variation in quality and to increase in efficiency of LCD assembly etc.
The above-mentioned laminated body is usually manufactured as a long size, and continually is cut by straight line and formed into an optical member with a predetermined size. In the case, minute cracks, smudges of adhesive layer, etc. occur in cut parts of the laminated bodies. Therefore, some measures are adopted in which after a smoothing processing for cut face is adopted by cutting etc. and then the laminated body is presented into a practical use (JP, 61-136746,A).
However, in a case the optical member by treated with the above-mentioned smoothing processing is presented for an assembly line of LCD etc., an adhesive layer exposed on a processing face is drawn out in a shape of strand by a contact of the processing face with conveyance instruments or by a friction of piled-up optical members being taken out, etc., to cause pollution with adhesives on a side face of the optical member. Since optical members are pulled with each other by adhesion of the pollution with adhesives, there occurred a problem that conveyance became impossible. Moreover, when the optical members are adhered to a display, the adhesive layer drawn out is entangled into the optical members to cause an defect in assembly, and sometimes break of adhesive in the adhesive layer occurred by the above-mentioned drawn-out of adhesives, and then there occurred a problem that induces a display interference as abnormal appearance etc.
The object of the present invention is to provide an optical member in which an adhesive layer exposed in a side face may not be easily drawn out by a contact to conveyance instruments or by a friction caused when the optical members are taken out from a piled state etc., and also conveyance interference in assembly line, break of adhesive in adhesive layer side face, a pollution with adhesives, a display interference may not be easily generated.
The present invention provides an optical member comprising a laminated body in which adhesive layer is prepared in an optical material, wherein a side face of the laminated body has a concavo-convex repeated structure by waveform, rectangle, trapezoid, or zigzagged form.
The present invention in the above-mentioned optical member, the concavo-convex repeated structure has a pitch from 0.2 to 20 mm, and a projected length of convex position from 0.1 to 10 mm.
The optical member in the above-mentioned optical member, the side face having the concavo-convex repeated structure occupies all surrounding of the laminated body or a part thereof.
The optical member in the above-mentioned optical member, the optical material comprises at least one of a polarizing plate, a retardation plate and a brightness enhanced plate.
In the present invention, since a side face has a concavo-convex repeated structure, it is prevented that an adhesive layer is drawn out by a contact to conveyance instruments, or by a friction caused at time of the optical member being taken out from piled state, and as a result an optical member can be obtained in which problems such as conveyance interference in assembly line, break of adhesive or pollution with adhesives in a side face of an adhesive layer etc. or display inhibition hardly occur. Moreover, since a side face having a concavo-convex repeated structure may be formed by cutting processing as punch processing etc., a method of the present invention excels also in manufacturing efficiency.